Semiconductor components, such as chip scale packages, BGA devices, flip chip devices, and bumped dice include terminal contacts such as bumps, balls, pins or pads. The terminal contacts can be formed directly on the dice, or on substrates attached to the dice. Typically, the components also include protective layers which insulate one or more surfaces of the dice, and provide electrical insulation for the terminal contacts, and for conductors associated with the terminal contacts. The quality, reliability and cost of these types of components are often dependent on the fabrication method for the terminal contacts.
As the components become smaller, and the terminal contacts more dense, fabrication methods become more difficult. In particular, reliable electrical connections must be made between the terminal contacts for the components, and die contacts on the dice contained within the components. Typically, the die contacts are thin film aluminum bond pads in electrical communication with integrated circuits. The intermediate connections between the die contacts and the terminal contacts are referred to herein as “interconnect contacts”.
One type of interconnect contact comprises wires bonded at one end to the die contacts, and at an opposing end to bonding pads in electrical communication with the terminal contacts. These interconnect contacts are relatively fragile and can separate from the die contacts and become entangled. Another type of interconnect contact includes conductors on a polymer substrate, similar to TAB tape, attached to the face of the dice. In this case the polymer substrate may be difficult to align and attach to the dice.
In addition to forming reliable interconnect contacts between the die contacts and the terminal contacts, it is preferable that the fabrication method be performed at the wafer level wherein multiple components are fabricated on a substrate, such as a wafer or a panel, which can then be singulated into individual components. Further, it is preferable that the fabrication method be capable of being performed using conventional equipment and materials.
The present invention is directed to an improved semiconductor component, and to a wafer level method for fabricating the component, in large volumes, at low costs, and with minimal defects.